Global analysis of depletion and recovery of seabed biota after bottom trawling disturbance

Bottom trawling is the most widespread human activity affecting seabed habitats. Here, we collate all available data for experimental and comparative studies of trawling impacts on whole communities of seabed macroinvertebrates on sedimentary habitats and develop widely applicable methods to estimate depletion and recovery rates of biota after trawling. Depletion of biota and trawl penetration into the seabed are highly correlated. Otter trawls caused the least depletion, removing 6% of biota per pass and penetrating the seabed on average down to 2.4 cm, whereas hydraulic dredges caused the most depletion, removing 41% of biota and penetrating the seabed on average 16.1 cm. Median recovery times posttrawling (from 50 to 95% of unimpacted biomass) ranged between 1.9 and 6.4 y. By accounting for the effects of penetration depth, environmental variation, and uncertainty, the models explained much of the variability of depletion and recovery estimates from single studies. Coupled with large-scale, high-resolution maps of trawling frequency and habitat, our estimates of depletion and recovery rates enable the assessment of trawling impacts on unprecedented spatial scales

Trawl fishing impacts on the status of seabed fauna in diverse regions of the globe

Bottom trawl fishing is a controversial activity. It yields about a quarter of the world's wild seafood, but also has impacts on the marine environment. Recent advances have quantified and improved understanding of large-scale impacts of trawling on the seabed. However, such information needs to be coupled with distributions of benthic invertebrates (benthos) to assess whether these populations are being sustained under current trawling regimes. This study collated data from 13 diverse regions of the globe spanning four continents. Within each region, we combined trawl intensity distributions and predicted abundance distributions of benthos groups with impact and recovery parameters for taxonomic classes in a risk assessment model to estimate benthos status. The exposure of 220 predicted benthos-group distributions to trawling intensity (as swept area ratio) ranged between 0% and 210% (mean = 37%) of abundance. However, benthos status, an indicator of the depleted abundance under chronic trawling pressure as a proportion of untrawled state, ranged between 0.86 and 1 (mean = 0.99), with 78% of benthos groups > 0.95. Mean benthos status was lowest in regions of Europe and Africa, and for taxonomic classes Bivalvia and Gastropoda. Our results demonstrate that while spatial overlap studies can help infer general patterns of potential risk, actual risks cannot be evaluated without using an assessment model that incorporates trawl impact and recovery metrics. These quantitative outputs are essential for sustainability assessments, and together with reference points and thresholds, can help managers ensure use of the marine environment is sustainable under the ecosystem approach to management

Community-based intervention packages for reducing maternal and neonatal morbidity and mortality and improving neonatal outcomes

Background: While maternal, infant and under-five child mortality rates in developing countries have declined significantly in the past two to three decades, newborn mortality rates have reduced much more slowly. While it is recognised that almost half of the newborn deaths can be prevented by scaling up evidence-based available interventions such as tetanus toxoid immunisation to mothers, clean and skilled care at delivery, newborn resuscitation, exclusive breastfeeding, clean umbilical cord care, management of infections in newborns, many require facility based and outreach services. It has also been stated that a significant proportion of these mortalities and morbidities could also be potentially addressed by developing community-based packages interventions which should also be supplemented by developing and strengthening linkages with the local health systems. Some of the recent community-based studies of interventions targeting women of reproductive age have shown variable impacts on maternal outcomes and hence it is uncertain if these strategies have consistent benefit across the continuum of maternal and newborn care.Objectives: To assess the effectiveness of community-based intervention packages in reducing maternal and neonatal morbidity and mortality, and improving neonatal outcomes.Search strategy: We searched The Cochrane Pregnancy and Childbirth Group\u27s Trials Register (January 2010), World Bank\u27s JOLIS (12 January 2010), BLDS at IDS and IDEAS database of unpublished working papers (12 January 2010), Google and Google Scholar (12 January 2010). Selection criteria: All prospective randomised and quasi-experimental trials evaluating the effectiveness of community-based intervention packages in reducing maternal and neonatal mortality and morbidities, and improving neonatal outcomes.Data collection and analysis: Two review authors independently assessed trial quality and extracted the data.Main results:The review included 18 cluster-randomised/quasi-randomised trials, covering a wide range of interventional packages, including two subsets from one trial. We incorporated data from these trials using generic inverse variance method in which logarithms of risk ratio estimates were used along with the standard error of the logarithms of risk ratio estimates. Our review did not show any reduction in maternal mortality (risk ratio (RR) 0.77, 95% confidence interval (CI) 0.59 to 1.02, random-effects (10 studies, n = 144,956), I(2) 39%, P value 0.10. However, significant reduction was observed in maternal morbidity (RR 0.75, 95% CI 0.61 to 0.92, random-effects (four studies, n = 138,290), I(2) 28%, neonatal mortality (RR 0.76, 95% CI 0.68 to 0.84, random-effects (12 studies, n = 136,425), I(2) 69%, P value \u3c 0.001), stillbirths (RR 0.84, 95% CI 0.74 to 0.97, random-effects (11studies, n = 113,821), I(2) 66%, P value 0.001) and perinatal mortality (RR 0.80, 95% CI 0.71 to 0.91, random-effects (10 studies, n = 110,291), I(2) 82%, P value \u3c 0.001) as a consequence of implementation of community-based interventional care packages. It also increased the referrals to health facility for pregnancy related complication by 40% (RR 1.40, 95% CI 1.19 to 1.65, fixed-effect (two studies, n = 22,800), I(2) 0%, P value 0.76), and improved the rates of early breastfeeding by 94% (RR 1.94, 95% CI 1.56 to 2.42, random-effects (six studies, n = 20,627), I(2) 97%, P value \u3c 0.001). We assessed our primary outcomes for publication bias, but observed no such asymmetry on the funnel plot.Authors\u27Conclusion:Our review offers encouraging evidence of the value of integrating maternal and newborn care in community settings through a range of interventions which can be packaged effectively for delivery through a range of community health workers and health promotion groups. While the importance of skilled delivery and facility-based services for maternal and newborn care cannot be denied, there is sufficient evidence to scale up community-based care through packages which can be delivered by a range of community-based workers

Teacher Professionalism and Continuing Professional Development: Contested Concepts and their Implications for School Leader

The aim of this chapter is to explore the ways in which contested notions of professionalism in a number of different countries influence the content and provision of continuing professional development (CPD) and to consider the implications of these conceptualisations of professionalism and CPD for school leaders